Binoculars

ABSTRACT

Binoculars having a prism assembly between the objective and ocular, wherein the prism assembly is secured on a prism holding device by means of a permanently elastic sealing compound.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention is directed to binoculars with a prismassembly between the objective and ocular.

[0003] 2. Background Art

[0004] These prism assemblies have two main functions, i.e., on one handthey rotate the side-inverted and upside-down image that is supplied bythe objective into the proper observation position, and on the otherhand they shorten the overall physical length of an optical system ofthis type. To be able to fulfill these functions, the rotating systemformed by the prisms is located between the objective and the commonfocal plane of the objective and ocular. In this context it is importantthat the rotating system remain permanently immovably fixed in itspre-adjusted position. Since prism assemblies have a relatively highinherent weight, their support must be designed very sturdy.

[0005] The attachment is conventionally implemented with adjustingscrews, fastening bows and by means of hard, inelastic adhesives, ifnecessary. This results in point-specific high stresses and tensions andthus in an adverse effect on the optical transmission. With higherstresses, such as blows, jolts, or if the binoculars are dropped, theresulting point-specific stresses often also result in a breaking of theprism assembly.

SUMMARY OF THE INVENTION

[0006] With this as the starting point, the invention has as its objectto create binoculars, or indicate a method for their production, wherebya fast, simple and very precise primary adjustment can be implementedduring the production, which furthermore assures that the prism assemblyis supported shock-proof when in use.

[0007] This object is met according to the invention in such a way thatthe prism assembly is fixed on a prism holding device by means of apermanently elastic sealing compound, preferably in the form of anacetic-acid-free compound on a silicone basis.

[0008] With this fastening technique, shock energy can be absorbed and,due to the elasticity and large working surface in the fastening range,occurring tensions that are triggered by temperature fluctuations,jolts, blows, and the like are very low.

[0009] This provides an improvement of the optical efficiency, a greatertemperature fluctuation tolerance range of the binoculars, a significantincrease in their robustness and, as a result, of course a reducedbreakdown rate. At the same time, the manufacture and primary adjustmentare simplified, as will be described in greater detail below.

[0010] Provision is advantageously made for the sealing compound to havea Shore hardness of approximately A 45, an elongation of approximately250%, as well as a shear strength of 1.2 MPa.

[0011] The space that is delimited by the ocular and the area of theprism assembly facing the ocular is advantageously provided with atleast one through opening. This through opening fulfills a dual functionin that a vacuum can be applied via the through opening(s) during theproduction, so that the prism assembly is suctioned against the prismholding device, which specifically has the shape of a support collar. Itis therefore possible to optically adjust the prism assembly during themanufacturing process in a very simple manner and to hold it positionedin the adjusted position in order to then perform a final securing bymeans of a permanently elastic sealing compound. After the sealingcompound has hardened and the prism assembly has been secured, this samethrough opening can be used to fill the space with nitrogen in a mannerknown per se.

[0012] The invention also pertains to a method for producing binoculars,specifically according to any of claims 1 through 5, which arecharacterized in that the prism assembly is positioned on the prismholding device, that a negative pressure is applied via a throughopening, and the prism assembly is pressed against a support surface ofthe prism holding device in this manner, that an optical adjustment isthen performed, and the adjusted position of the prism assembly issecured.

[0013] Provision is made in particular for the securing of the prismassembly to take place with a quick-curing, specifically a UV-curable,sealing compound.

[0014] The permanently elastic sealing compound is entered specificallyinto a remaining free space between the prism holding device and prismassembly. This creates a large fastening surface that prevents peakloads.

[0015] The use of a sealing compound in the form of an acetic-acid-freecompound on a silicon basis prevents the exhalation of acetic acid andthus any resulting stress on the optical system, and on the other hand,it produces the desired elastic support.

[0016] The invention will be explained in more detail below based on apreferred embodiment in conjunction with the drawing.

BRIEF DESCRIPTION OF THE DRAWING

[0017]FIG. 1 shows a longitudinal section through the area between theobjective and prism assembly of a pair of binoculars, and

[0018]FIG. 2 shows a view in the perspective of the prism assembly of apair of inventive binoculars.

DESCRIPTION OF THE PREFERRED EMBODIMENT

[0019]FIG. 1 shows a longitudinal section through the area of theso-called prism seat 1 of a pair of binoculars 2, wherein an objective 3is disposed on the front end of the prism seat 1, which is shown as theright end in the drawing, and a prism assembly 4 is disposed on the leftend. Between the prism assembly 4, objective 3, and prism seat 1, aninterior space 5 is formed, which is provided with a through opening 6.The prism assembly rests on the prism seat via a collar-shaped supportsurface 7 with a sealing lip 8. Between the outer face 9, the prismassembly, and an annular collar 10 of the prism seat, an annular freespace 11 is formed that is filled with a permanently elastic sealingcompound 12.

[0020] In the course of the production, the prism assembly 4 is placedupon the support surface 7 in a position that is rotated 90° to theright from FIG. 1, and a vacuum is applied via the through opening 6, sothat the prism assembly 4 is pressed against the sealing lip 8. Anoptically correct positioning of the prism assembly 4 now takes placerelative to the objective 3. As soon as this adjustment has been made(which eliminates the need to manipulate any adjustment screws), thepermanently elastic sealing compound 11 is entered and hardened throughUV radiation. Nitrogen is then introduced through the through opening 6and the through opening 6 is sealed.

What is claimed is:
 1. Binoculars (2) having a prism assembly (4)between the objective and ocular, wherein the prism assembly (4) issecured on a prism holding device by means of a permanently elasticsealing compound (12).
 2. Binoculars (2) according to claim 1, whereinthe sealing compound (12) is an acetic-acid-free compound on a siliconbasis.
 3. Binoculars (2) according to claim 1, wherein the sealingcompound (12) has a Shore hardness of approximately A 45 and anelongation of approximately 250%.
 4. Binoculars (2) according to claim2, wherein the shear strength is approximately 1.2 MPa.
 5. Binoculars(2) according to claim 1, wherein the space (5) that is delimited by theocular and the area of the prism assembly facing the ocular incorporatesat least one through opening (6).
 6. A method for producing binoculars(2) according to claim 1, wherein the prism assembly (4) is positionedon the prism holding device, that a negative pressure is applied via thethrough opening (6) and the prism assembly (4) is thus pressed against asupport surface of the prism holding device, that an optical adjustmentis then performed and the adjusted position of the prism assembly (4) issecured.
 7. Binoculars (2) according to claim 6, wherein the securing ofthe prism assembly (4) takes place with a quick-curing, specifically aUV-curable, sealing compound (12).
 8. Binoculars (2) according to claim6, wherein the permanently elastic sealing compound (12) is entered intoa remaining free space (11) between the prism holding device and prismassembly (4).